Rolling-mill rolls are known with two stub shafts rotationally coupled to journal bearings so as to resist torque at limited axial regions by keys. According to DE 26 12 744 [U.S. Pat. No. 4,093,321], the keys are provided outside the region of the roll pressure force acting on the journal bushing. A rolling-mill roll with a journal bushing mounted to resist torque by a key is also known from WO 2007 134655 [US 2009/0116774]. The key or its groove is here very close to the Rotscher line delimiting the outer area of the compressive force transmission. The keys are of greater radial than axial dimension. This is designed to result in a short configuration of the rolls. Furthermore, the width of the roll stand is hereby reduced, which is associated with narrower substructures, narrower rolling mill bays and rolling mill workshops.
On the other hand, a water-cooled furnace roll for conveying thin slabs is known from DE 100 07 383 that is used in particular in the hot zone of a roll hearth furnace. The furnace roll comprises a shaft that rotatably driven and is supported outside the furnace, the shaft having interior passages for throughflow of cooling water. The shaft has support parts for rings that carry the thin slabs with rings whose outer surfaces are of polygonal cross section, each ring being formed with a complementary inner surface. The polygonal cross section of the shaft can also extend over the bearing length of the shaft.